[jetboy]

Let's throw out some typical final drives: 3.545, 3.7, 3.9, 4.11, 4.44 ...

1) Is this an exchange in the final gearset, most often the differential?

2) Does this ratio mean that i.e 3.545 rotations of the flywheel means one rotation of the driven wheel?

3) Is final drive always engaged or is it "overdrive" after the 4th gear. i.e will the 3.545:1 ratio only stand true when the transmission (4EAT here of course) is in 4th gear?

If such is the case, then 3.545:1 means lower RPM at high speeds = less noise, less fuel consumed compared to 4.44:1 ?

I read here somewhere that 4.44 gave better accelleration. Does this mean that the higher final drive ratio, the shorter the gears are?

Why does 3.90 seem to be a magic number? Because it's a tradeoff between comfort and performance?